Max number of threads [1024] for user [elasticsearch] is too low

Elastic Stack Elasticsearch
1

I am using Centos and I start the elasticsearch as as service from root user .
despite these settings I am still getting the warning of max number of threads too low.

I have put the following lines in the /etc/security/limits.conf

elasticsearch - nofile 65536
root - nofile 65536

and in /etc/sysconfig/elasticsearch I have put the following

MAX_OPEN_FILES=65536

and in /usr/lib/system/system/elasticsearch.service

[root@hadoop1 ~]# grep LimitNOFILE /usr/lib/systemd/system/elasticsearch.service
LimitNOFILE=65536

2

The error message is not about the maximum number of open files, but about the number of threads that the user can spawn.

3 
*    soft    nofile    655350
*    hard    nofile    655350
* hard nproc 655350
* soft nproc 655350
* hard nofile 500000
* soft nofile 500000
* hard stack 327680
* soft stack 102400

set link this.